The gold and silver keys require you to use certain items or find secret areas, the gold and silver keys lead to storage areas where you can top yourself up on health, but the Emerald key is much more special.

Silver Key: Distraction course in the Truth Chamber.

Gold Key: Prize for playing the right tune on the red piano.

Emerald Key: Above the code blocks in the Uben Fortress, but you can only obtain it later on.

How do I play the tunes in the piano rooms?

Since these are hard if you don't have any music knowledge and/or never learned how to play these tunes, I will give you the notes here:

Red piano:
C G G F E D C(octave) G G F E D C(octave) G G F E F D

Blue Piano:
E D C D E E E D D D E G G

Green Piano:
A A A F A C(Octave) C

I have been told to buy a Scarab Stone, but where can I find it?

The Scarab Stone shop is located in "Sunlight Night". In the second area there are walls in which you can walk through, that area isn't big so it won't take long to find.

I have bought the Scarab Stone but I don't know where to use it.

If you didn't already open the level 'Run-Down Village' then you need to go and find the secret exit in the Uben Pyramid. Once in the Run-Down Village, you will talk to a villager who says something about a window being too to get in, well it's pretty obvious what to do from here.

The 5 riddles are too confusing, where am I supposed to go?

Before even trying the riddles it would probably be best to open up the normal path level, this means you don't need to open the secret levels. When reading the riddles, make sure you read them thoroughly, and think hard to try and remember which level had all the things mentioned in the riddle.

The clues that the riddles lead me to don't make sense, what do I read from these?

Basically, you read the clue, then take from it the symbol that it mentions (Sun, moon, star, diamond, eye) and also the number so what you are left with is the symbol block and how many times to hit it.

But where do I apply the code once I have figured out the 5 clues?

Remember the Uben Temples' big door with the 5 symbol blocks before it, well that is where you input the code, if you have got it right, then you will be able to go through that door.